The invention relates to a folding vehicle roof for a motor vehicle, particularly a passenger car, with roof elements which are movable relative to a base structure and of which one roof element supports an adjacent roof element and both are supported by four-link operating mechanisms.
DE 101 08 493 A1 discloses a folding roof of this type with several roof elements which are displaceable with respect to the vehicle body on which they are supported. The roof elements comprise a front part disposed adjacent the windshield frame, a center part and a rear part. The front part, which in the longitudinal vehicle direction, is disposed adjacent the center part is supported by the adjacent center part. The center part again is supported on the vehicle body by means of a four-link operating mechanism including two pivot arms which extend parallel and in spaced relationship and are pivotally connected to the vehicle body. One of the two pivot arms forms a drive arm and is connected by way of guide links in the form of a parallelogram-like pair of support arms with the transfer arm, which supports the front part on the support element of the center part. The arm of the parallelogram-type pair of support arms is firmly connected to the center part and carries the connecting points of the four-link operating mechanism on the center part, whereas the other arm of the parallelogram-type pair of support arms is adjustable relative to the center part in the longitudinal vehicle direction by way of its connection to the drive arm and the transfer arm.
In the area where this adjustable arm is connected to the transfer arm, a step-up transmission structure is provided which is in the form of an additional four-link mechanism and includes a link which interconnects the arms of the parallelogram-type pair of support arms and which is disposed adjacent the transfer arm and extends about parallel thereto.
The four-link operating mechanism which interconnects the center part and the support structure that is the vehicle body, forms with the drive arm also the support for the rear roof part of the vehicle roof, which generally includes the rear window and which, with the roof open, is disposed in a storage compartment upside down below the center part and the front part. The front and center roof parts are disposed in the storage compartment stacked on top of one another in their original orientation and on top of the rear part.
The arrangement of the support linkage interconnecting the four-link operating mechanism and the pivot support thereof with respect to the support linkage provide, in connection with the respective dimensioning and arrangement of the individual transfer members of the four-link operating mechanism formed by the support arms and linkages, with the desired space-saving and flat construction, disadvantageous transfer ratios or conditions, which result in high joint forces in the respective support joints and a relatively complicated design.
It is the object of the present invention to provide a vehicle roof of the type described in the introductory part, which however is simple in its design and provides for advantageous load or stress conditions particularly in the joints and linkage points which are subjected to the operating forces.